Crop Science Department, Damanhur University, Damanhur, Egypt.
Department of Agronomy and Horticulture, University of Nebraska, Lincoln, NE, United States of America.
PLoS One. 2019 Nov 13;14(11):e0222755. doi: 10.1371/journal.pone.0222755. eCollection 2019.
Stripe rust (incited by Puccinia striiformis f. sp. tritici) is airborne wheat (Triticum aestivum L.) disease with dynamic virulence evolution. Thus, anticipatory and continued screening in hotspot regions is crucial to identify new pathotypes and integrate new resistance resources to prevent potential disease epidemics. A global wheat panel consisting of 882 landraces and 912 improved accessions was evaluated in two locations in Egypt during 2016 and 2017. Five prevalent and aggressive pathotypes of stripe rust were used to inoculate the accessions during the two growing seasons and two locations under field conditions. The objectives were to evaluate the panel for stripe rust resistance at the adult plant stage, identify potentially novel QTLs associated with stripe rust resistance, and validate previously reported stripe rust QTLs under the Egyptian conditions. The results indicated that 42 landraces and 140 improved accessions were resistant to stripe rust. Moreover, 24 SNPs were associated with stripe rust resistance and were within 18 wheat functional genes. Four of these genes were involved in several plant defense mechanisms. The number of favorable alleles, based upon the associated SNPs, was significant and negatively correlated with stripe rust resistance score, i.e., as the number of resistances alleles increased the observed resistance increased. In conclusion, generating new stripe rust phenotypic information on this panel while using the publicly available molecular marker data, contributed to identifying potentially novel QTLs associated with stripe rust and validated 17 of the previously reported QTLs in one of the global hotspots for stripe rust.
条锈病（由小麦条锈菌引起）是一种具有动态毒力进化的气传小麦病害。因此，在热点地区进行预期和持续的筛选对于鉴定新的生理小种和整合新的抗性资源以防止潜在的疾病流行至关重要。在 2016 年和 2017 年，在埃及的两个地点评估了一个由 882 个地方品种和 912 个改良品种组成的全球小麦小组。在两个生长季节和两个田间条件下，使用五个流行和侵袭性的条锈病生理小种对这些品种进行接种。目的是评估该小组在成株期对条锈病的抗性，鉴定与条锈病抗性相关的潜在新 QTL，并在埃及条件下验证先前报道的条锈病 QTL。结果表明，42 个地方品种和 140 个改良品种对条锈病具有抗性。此外，有 24 个 SNP 与条锈病抗性相关，位于 18 个小麦功能基因内。其中 4 个基因参与了几种植物防御机制。基于相关 SNP 的有利等位基因数量显著且与条锈病抗性评分呈负相关，即随着抗性等位基因数量的增加，观察到的抗性增加。总之，在这个小组中生成新的条锈病表型信息，同时利用公开的分子标记数据，有助于鉴定与条锈病相关的潜在新 QTL，并在条锈病的一个全球热点之一中验证了 17 个先前报道的 QTL。
